Business Combinations (Narrative) (Details) $ in Thousands							3 Months Ended		9 Months Ended
	Jun. 02, 2015 USD ($)	Mar. 02, 2015 Companies	Dec. 02, 2014 USD ($)	Nov. 03, 2014 USD ($)	May. 21, 2014 USD ($)	Jan. 27, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Jun. 01, 2015 USD ($)	Mar. 01, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 01, 2014 USD ($)	Dec. 31, 2013 USD ($)
Business Acquisition [Line Items]
Document Period End Date									Sep. 30, 2015
Reduction of acquisition earnout accruals							$ (1,533)	$ (7,533)	$ (1,533)	$ (7,533)
Derivative Liability							8,013		8,013				$ 5,367		$ 14,420
Business acquisition, contingent consideration, at fair value, noncurrent							6,323		6,323				4,480
Business acquisition, contingent consideration, at fair value, current							1,690		1,690				887
Goodwill							408,093		408,093				402,220		$ 337,068
Via Media Health and PB Systems [Member]
Business Acquisition [Line Items]
Number of businesses acquired | Companies		2
Via Media Health [Member]
Business Acquisition [Line Items]
Purchase Price of Business Acquisition, Cost of Acquired Entity												$ 1,000
Derivative, Term of Contract		24 months
PB Systems [Member]
Business Acquisition [Line Items]
Derivative, Term of Contract	24 months
Payments to Acquire Businesses, Gross	$ 12,400
Oakstone [Member]
Business Acquisition [Line Items]
Payments to Acquire Business, Net			$ 23,720
Payments to Acquire Businesses, Gross			31,370
Net working capital adjustment			7,650
Goodwill			28,769
Deferred Revenue			6,500
Oakstone [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)			1,691
Oakstone [Member] | Developed technology [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)			501
i3 [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross			$ 2,000
Goodwill														$ 1,600
i3 [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)														310
i3 [Member] | Developed technology [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)														48
Vertex [Member]
Business Acquisition [Line Items]
Derivative, Term of Contract				24 months
Payments to Acquire Businesses, Gross				$ 27,250
Goodwill				27,728
Vertex [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)				2,502
Vertex [Member] | Developed technology [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)				$ 235
Healthcare Magic [Member]
Business Acquisition [Line Items]
Derivative Liability							596		596
Derivative, Term of Contract					24 months
Payments to Acquire Businesses, Gross					$ 6,000
Goodwill					5,619
Healthcare Magic [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)					452
Healthcare Magic [Member] | Developed technology [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)					100
Healthcare Magic [Member] | Trademarks and Trade Names [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)					59
Healthcare Magic [Member] | Non-compete agreements [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)					226
Curepet, Inc. [Member]
Business Acquisition [Line Items]
Purchase Price of Business Acquisition, Cost of Acquired Entity						$ 6,350
Derivative Liability						5,000	0		0
Purchase Price of Business acquisition, Non-Cash portion of Acquired Entity						$ 1,350
Derivative, Term of Contract						36 months
Contingent Accrued Earn-out Acquisition Consideration [Member]
Business Acquisition [Line Items]
Derivative Liability							8,013		8,013				5,367
Business acquisition, contingent consideration, at fair value, noncurrent							6,300		6,300				4,500
Business acquisition, contingent consideration, at fair value, current							$ 1,700		$ 1,700				$ 900
Maximum [Member] | Via Media Health [Member]
Business Acquisition [Line Items]
Derivative Liability												$ 372
Maximum [Member] | PB Systems [Member]
Business Acquisition [Line Items]
Derivative Liability											$ 8,000
Maximum [Member] | i3 [Member]
Business Acquisition [Line Items]
Derivative Liability														4,000
Maximum [Member] | Vertex [Member]
Business Acquisition [Line Items]
Derivative Liability														$ 2,000
Maximum [Member] | Healthcare Magic [Member]
Business Acquisition [Line Items]
Derivative Liability					$ 12,360
Maximum [Member] | Curepet, Inc. [Member]
Business Acquisition [Line Items]
Derivative Liability						$ 5,000